51
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Tucker IG, Yang L, Mujoo H. Delivery of drugs to the brain via the blood brain barrier using colloidal carriers. J Microencapsul 2012; 29:475-86. [PMID: 22563886 DOI: 10.3109/02652048.2012.658445] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Delivering drugs to the brain is challenging given the selective permeability of the blood brain barrier (BBB). Targeted colloidal carriers containing drug payloads offer some promise for enhanced and perhaps selective delivery to brain. This review examines the recent literature and identifies issues to be addressed if these systems are to be rationally designed. These include opsonization of nanoparticles and off-target clearance; the cerebral microvasculature, flow of nanoparticles in capillaries and binding to the capillary wall; and transcytosis. Capillary architecture, blood flow and BBB permeability are affected by disease and age and there are species differences. These complexities caution against making extravagant claims for a particular nanosystem but they also highlight the rich opportunities and need for critical research in this field.
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Affiliation(s)
- Ian G Tucker
- School of Pharmacy, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
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52
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Poduslo JF, Howell KG, Olson NC, Ramirez-Alvarado M, Kandimalla KK. Alzheimer’s Disease Amyloid β-Protein Mutations and Deletions That Define Neuronal Binding/Internalization as Early Stage Nonfibrillar/Fibrillar Aggregates and Late Stage Fibrils. Biochemistry 2012; 51:3993-4003. [DOI: 10.1021/bi300275g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joseph F. Poduslo
- Departments of Neurology, Neuroscience,
and Biochemistry/Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - Kyle G. Howell
- Departments of Neurology, Neuroscience,
and Biochemistry/Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - Nicole C. Olson
- Departments of Neurology, Neuroscience,
and Biochemistry/Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - Marina Ramirez-Alvarado
- Departments of Neurology, Neuroscience,
and Biochemistry/Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - Karunya K. Kandimalla
- Departments of Neurology, Neuroscience,
and Biochemistry/Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, United States
- Department of Pharmaceutics,
College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, United States
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53
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Grabrucker AM, Schmeisser MJ, Udvardi PT, Arons M, Schoen M, Woodling NS, Andreasson KI, Hof PR, Buxbaum JD, Garner CC, Boeckers TM. Amyloid beta protein-induced zinc sequestration leads to synaptic loss via dysregulation of the ProSAP2/Shank3 scaffold. Mol Neurodegener 2011; 6:65. [PMID: 21939532 PMCID: PMC3189132 DOI: 10.1186/1750-1326-6-65] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 09/22/2011] [Indexed: 01/14/2023] Open
Abstract
Background Memory deficits in Alzheimer's disease (AD) manifest together with the loss of synapses caused by the disruption of the postsynaptic density (PSD), a network of scaffold proteins located in dendritic spines. However, the underlying molecular mechanisms remain elusive. Since it was shown that ProSAP2/Shank3 scaffold assembly within the PSD is Zn2+-dependent and that the amyloid beta protein (Aβ) is able to bind Zn2+, we hypothesize that sequestration of Zn2+ ions by Aβ contributes to ProSAP/Shank platform malformation. Results To test this hypothesis, we designed multiple in vitro and in vivo assays demonstrating ProSAP/Shank dysregulation in rat hippocampal cultures following Aβ oligomer accumulation. These changes were independent from alterations on ProSAP/Shank transcriptional level. However, application of soluble Aβ prevented association of Zn2+ ions with ProSAP2/Shank3 in a cell-based assay and decreased the concentration of Zn2+ clusters within dendrites. Zn2+ supplementation or saturation of Aβ with Zn2+ ions prior to cell treatment was able to counter the effects induced by Aβ on synapse density and ProSAP2/Shank3 levels at the PSD. Interestingly, intracellular Zn2+ levels in APP-PS1 mice and human AD hippocampus are reduced along with a reduction in synapse density and synaptic ProSAP2/Shank3 and Shank1 protein levels. Conclusions We conclude that sequestration of Zn2+ ions by Aβ significantly contributes to changes in ProSAP2/Shank3 platforms. These changes in turn lead to less consolidated (mature) synapses reflected by a decrease in Shank1 protein levels at the PSD and decreased synapse density in hippocampal neurons.
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Affiliation(s)
- Andreas M Grabrucker
- Institute for Anatomy and Cell Biology, Ulm University, Albert Einstein Allee 11, Ulm, 89081, Germany.
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54
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Infection of primary neurons mediated by nipah virus envelope proteins: role of host target cells in antiviral action. J Virol 2011; 85:8422-6. [PMID: 21653662 DOI: 10.1128/jvi.00452-11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We have previously described heterotypic peptides from parainfluenza virus that potently inhibit Nipah virus in vitro but are not efficacious in vivo. In contrast, our second-generation inhibitors, featuring a cholesterol moiety, are also efficacious in vivo. The difference between in vitro and in vivo results led us to investigate the basis for this discrepancy. Here, we compare the activities of the compounds in standard laboratory cells and in cells relevant to the natural tropism of Nipah virus, i.e., primary neurons, and show that while our first-generation inhibitors are poorly active in primary neurons, the cholesterol-conjugated compounds are highly potent. These results highlight the advantage of evaluating antiviral potency in cells relevant to natural host target tissue.
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55
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Negis Y, Unal AY, Korulu S, Karabay A. Cell cycle markers have different expression and localization patterns in neuron-like PC12 cells and primary hippocampal neurons. Neurosci Lett 2011; 496:135-40. [DOI: 10.1016/j.neulet.2011.03.100] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 02/23/2011] [Accepted: 03/31/2011] [Indexed: 12/18/2022]
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56
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Binding studies of truncated variants of the Aβ peptide to the V-domain of the RAGE receptor reveal Aβ residues responsible for binding. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:592-609. [DOI: 10.1016/j.bbapap.2011.02.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Revised: 02/15/2011] [Accepted: 02/18/2011] [Indexed: 11/20/2022]
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57
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Lai AY, McLaurin J. Mechanisms of amyloid-Beta Peptide uptake by neurons: the role of lipid rafts and lipid raft-associated proteins. Int J Alzheimers Dis 2010; 2011:548380. [PMID: 21197446 PMCID: PMC3010653 DOI: 10.4061/2011/548380] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Accepted: 11/29/2010] [Indexed: 12/19/2022] Open
Abstract
A hallmark pathological feature of Alzheimer's disease (AD) is the accumulation of extracellular plaques composed of the amyloid-beta (Aβ) peptide. Thus, classically experiments were designed to examine Aβ toxicities within the central nervous system (CNS) from the extracellular space. However, a significant amount of evidence now suggests that intraneuronal accumulation of Aβ is neurotoxic and may play an important role in the disease progression of AD. One of the means by which neurons accumulate intracellular Aβ is through uptake of extracellular Aβ peptides, and this process may be a potential link between Aβ generation, synaptic dysfunction, and AD pathology. Recent studies have found that neuronal internalization of Aβ involves lipid rafts and various lipid raft-associated receptor proteins. Uptake mechanisms independent of lipid rafts have also been implicated. The aim of this paper is to summarize these findings and discuss their significance in the pathogenesis of AD.
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Affiliation(s)
- Aaron Y Lai
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, 6 Queen's Park Crescent West, Toronto, ON, Canada M5S 3H2
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58
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Dafnis I, Stratikos E, Tzinia A, Tsilibary EC, Zannis VI, Chroni A. An apolipoprotein E4 fragment can promote intracellular accumulation of amyloid peptide beta 42. J Neurochem 2010; 115:873-84. [PMID: 20412390 DOI: 10.1111/j.1471-4159.2010.06756.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Apolipoprotein E (apoE) plays a crucial role in lipid transport in circulation and the brain. The apoE4 isoform is a major risk factor for Alzheimer's disease (AD). ApoE4 is more susceptible to proteolysis than other apoE isoforms and apoE4 fragments have been found in brains of AD patients. These apoE4 fragments have been hypothesized to be involved in the pathogenesis of AD, although the mechanism is not clear. In this study we examined the effect of lipid-free apoE4 on amyloid precursor protein processing and 40-amino-acid Aβ variant and 42-amino-acid Aβ variant levels in human neuroblastoma SK-N-SH cells. We discovered that a specific apoE4 fragment, apoE4[Δ(166-299)], can promote the cellular uptake of extracellular 40-amino-acid Aβ variant and 42-amino-acid Aβ variant either generated after amyloid precursor protein transfection or added exogenously. A longer length fragment, apoE4[Δ(186-299)], or full-length apoE4 failed to elicit this effect. ApoE4[Δ(166-299)] effected a 20% reduction of cellular sphingomyelin levels, as well as changes in cellular membrane micro-fluidity. Following uptake, approximately 50% of 42-amino-acid Aβ variant remained within the cell for at least 24 h, and led to increased formation of reactive oxygen species. Overall, our findings suggest a direct link between two early events in the pathogenesis of AD, apoE4 proteolysis and intraneuronal presence of amyloid beta peptide.
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Affiliation(s)
- Ioannis Dafnis
- Institute of Biology, National Center for Scientific Research Demokritos, Athens, Greece
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59
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Nielsen HM, Mulder SD, Beliën JAM, Musters RJP, Eikelenboom P, Veerhuis R. Astrocytic A beta 1-42 uptake is determined by A beta-aggregation state and the presence of amyloid-associated proteins. Glia 2010; 58:1235-46. [PMID: 20544859 DOI: 10.1002/glia.21004] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Intracerebral accumulation of amyloid-beta (A beta) leading to A beta plaque formation, is the main hallmark of Alzheimer's disease and might be caused by defective A beta-clearance. We previously found primary human astrocytes and microglia able to bind and ingest A beta 1-42 in vitro, which appeared to be limited by A beta 1-42 fibril formation. We now confirm that astrocytic A beta-uptake depends on size and/or composition of A beta-aggregates as astrocytes preferably take up oligomeric A beta over fibrillar A beta. Upon exposure to either fluorescence-labelled A beta 1-42 oligomers (A beta(oligo)) or fibrils (A beta(fib)), a larger (3.7 times more) proportion of astrocytes ingested oligomers compared to fibrils, as determined by flow cytometry. A beta-internalization was verified using confocal microscopy and live-cell imaging. Neither uptake of A beta(oligo) nor A beta(fib), triggered proinflammatory activation of the astrocytes, as judged by quantification of interleukin-6 and monocyte-chemoattractant protein-1 release. Amyloid-associated proteins, including alpha1-antichymotrypsin (ACT), serum amyloid P component (SAP), C1q and apolipoproteins E (ApoE) and J (ApoJ) were earlier found to influence A beta-aggregation. Here, astrocytic uptake of A beta(fib) increased when added to the cells in combination with SAP and C1q (SAP/C1q), but was unchanged in the presence of ApoE, ApoJ and ACT. Interestingly, ApoJ and ApoE dramatically reduced the number of A beta(oligo)-positive astrocytes, whereas SAP/C1q slightly reduced A beta(oligo) uptake. Thus, amyloid-associated proteins, especially ApoJ and ApoE, can alter A beta-uptake in vitro and hence may influence A beta clearance and plaque formation in vivo.
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Affiliation(s)
- Henrietta M Nielsen
- Department of Clinical Chemistry, VU University Medical Center Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands.
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60
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Tillement L, Lecanu L, Papadopoulos V. Alzheimer's disease: effects of β-amyloid on mitochondria. Mitochondrion 2010; 11:13-21. [PMID: 20817045 DOI: 10.1016/j.mito.2010.08.009] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 08/09/2010] [Accepted: 08/25/2010] [Indexed: 11/15/2022]
Abstract
The impairment of the respiratory chain or defects in the detoxification system can decrease electron transfer efficiency, reduce ATP production, and increase reactive oxygen species (ROS) production by mitochondria. Accumulation of ROS results in oxidative stress, a hallmark of neurodegenerative diseases such as Alzheimer's disease (AD). β-amyloid has been implicated in the pathogenesis of AD, and its accumulation may lead to degeneration of neuronal or non-neuronal cells. There is evidence that β-amyloid interacts with mitochondria but little is known concerning the significance of this interaction in the physiopathology of AD. This review explores possible mechanisms of β-amyloid-induced mitochondrial toxicity.
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Affiliation(s)
- Laurent Tillement
- Department of Biochemistry and Molecular Biology, Georgetown University School of Medicine, Washington, DC 20057, USA
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61
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Singh TD, Park SY, Bae JS, Yun Y, Bae YC, Park RW, Kim IS. MEGF10 functions as a receptor for the uptake of amyloid-β. FEBS Lett 2010; 584:3936-42. [DOI: 10.1016/j.febslet.2010.08.050] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 07/31/2010] [Accepted: 08/30/2010] [Indexed: 10/19/2022]
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62
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Synaptotoxicity of Alzheimer beta amyloid can be explained by its membrane perforating property. PLoS One 2010; 5:e11820. [PMID: 20676404 PMCID: PMC2910737 DOI: 10.1371/journal.pone.0011820] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Accepted: 06/24/2010] [Indexed: 12/12/2022] Open
Abstract
The mechanisms that induce Alzheimer's disease (AD) are largely unknown thereby deterring the development of disease-modifying therapies. One working hypothesis of AD is that Aβ excess disrupts membranes causing pore formation leading to alterations in ionic homeostasis. However, it is largely unknown if this also occurs in native brain neuronal membranes. Here we show that similar to other pore forming toxins, Aβ induces perforation of neuronal membranes causing an increase in membrane conductance, intracellular calcium and ethidium bromide influx. These data reveal that the target of Aβ is not another membrane protein, but that Aβ itself is the cellular target thereby explaining the failure of current therapies to interfere with the course of AD. We propose that this novel effect of Aβ could be useful for the discovery of anti AD drugs capable of blocking these “Aβ perforates”. In addition, we demonstrate that peptides that block Aβ neurotoxicity also slow or prevent the membrane-perforating action of Aβ.
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63
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Tampellini D, Gouras GK. Synapses, synaptic activity and intraneuronal abeta in Alzheimer's disease. Front Aging Neurosci 2010; 2. [PMID: 20725518 PMCID: PMC2912028 DOI: 10.3389/fnagi.2010.00013] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Accepted: 03/12/2010] [Indexed: 01/05/2023] Open
Abstract
β-Amyloid peptide accumulation plays a central role in the pathogenesis of Alzheimer's disease. Aberrant β-amyloid buildup in the brain has been shown to be present both in the extracellular space and within neurons. Synapses are important targets of β-amyloid, and alterations in synapses better correlate with cognitive impairment than amyloid plaques or neurofibrillary tangles. The link between β-amyloid and synapses became even tighter when it was discovered that β-amyloid accumulates within synapses and that synaptic activity modulates β-amyloid secretion. Currently, a central question in Alzheimer's disease research is what role synaptic activity plays in the disease process, and how specifically β-amyloid is involved in the synaptic dysfunction that characterizes the disease.
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Affiliation(s)
- Davide Tampellini
- Department of Neurology and Neuroscience, Weill Cornell Medical College New York, NY, USA
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64
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Yu C, Nwabuisi-Heath E, Laxton K, Ladu MJ. Endocytic pathways mediating oligomeric Abeta42 neurotoxicity. Mol Neurodegener 2010; 5:19. [PMID: 20478062 PMCID: PMC2881055 DOI: 10.1186/1750-1326-5-19] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 05/17/2010] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND One pathological hallmark of Alzheimer's disease (AD) is amyloid plaques, composed primarily of amyloid-beta peptide (Abeta). Over-production or diminished clearance of the 42 amino acid form of Abeta (Abeta42) in the brain leads to accumulation of soluble Abeta and plaque formation. Soluble oligomeric Abeta (oAbeta) has recently emerged to be as a likely proximal cause of AD. RESULTS Here we demonstrate that endocytosis is critical in mediating oAbeta42-induced neurotoxicity and intraneuronal accumulation of Abeta. Inhibition of clathrin function either with a pharmacological inhibitor, knock-down of clathrin heavy chain expression, or expression of the dominant-negative mutant of clathrin-assembly protein AP180 did not block oAbeta42-induced neurotoxicity or intraneuronal accumulation of Abeta. However, inhibition of dynamin and RhoA by expression of dominant negative mutants reduced neurotoxicity and intraneuronal Abeta accumulation. Pharmacologic inhibition of the dynamin-mediated endocytic pathway by genistein also reduced neurotoxicity. CONCLUSIONS These data suggest that dynamin-mediated and RhoA-regulated endocytosis are integral steps for oligomeric Abeta42-induced neurotoxicity and intraneuronal Abeta accumulation.
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Affiliation(s)
- Chunjiang Yu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612 USA.
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65
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Poduslo JF, Gilles EJ, Ramakrishnan M, Howell KG, Wengenack TM, Curran GL, Kandimalla KK. HH domain of Alzheimer's disease Abeta provides structural basis for neuronal binding in PC12 and mouse cortical/hippocampal neurons. PLoS One 2010; 5:e8813. [PMID: 20098681 PMCID: PMC2809098 DOI: 10.1371/journal.pone.0008813] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 12/22/2009] [Indexed: 11/18/2022] Open
Abstract
A key question in understanding AD is whether extracellular Aβ deposition of parenchymal amyloid plaques or intraneuronal Aβ accumulation initiates the AD process. Amyloid precursor protein (APP) is endocytosed from the cell surface into endosomes where it is cleaved to produce soluble Aβ which is then released into the brain interstitial fluid. Intraneuronal Aβ accumulation is hypothesized to predominate from the neuronal uptake of this soluble extracellular Aβ rather than from ER/Golgi processing of APP. We demonstrate that substitution of the two adjacent histidine residues of Aβ40 results in a significant decrease in its binding with PC12 cells and mouse cortical/hippocampal neurons. These substitutions also result in a dramatic enhancement of both thioflavin-T positive fibril formation and binding to preformed Aβ fibrils while maintaining its plaque-binding ability in AD transgenic mice. Hence, alteration of the histidine domain of Aβ prevented neuronal binding and drove Aβ to enhanced fibril formation and subsequent amyloid plaque deposition - a potential mechanism for removing toxic species of Aβ. Substitution or even masking of these Aβ histidine residues might provide a new therapeutic direction for minimizing neuronal uptake and subsequent neuronal degeneration and maximizing targeting to amyloid plaques.
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Affiliation(s)
- Joseph F Poduslo
- Molecular Neurobiology Laboratory, Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
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66
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Tokuraku K, Marquardt M, Ikezu T. Real-time imaging and quantification of amyloid-beta peptide aggregates by novel quantum-dot nanoprobes. PLoS One 2009; 4:e8492. [PMID: 20041162 PMCID: PMC2794548 DOI: 10.1371/journal.pone.0008492] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Accepted: 12/01/2009] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Protein aggregation plays a major role in the pathogenesis of neurodegenerative disorders, such as Alzheimer's disease. However, direct real-time imaging of protein aggregation, including oligomerization and fibrillization, has never been achieved. Here we demonstrate the preparation of fluorescent semiconductor nanocrystal (quantum dot; QD)-labeled amyloid-beta peptide (QDAbeta) and its advanced applications. METHODOLOGY/PRINCIPAL FINDINGS The QDAbeta construct retained Abeta oligomer-forming ability, and the sizes of these oligomers could be estimated from the relative fluorescence intensities of the imaged spots. Both QDAbeta coaggregation with intact Abeta42 and insertion into fibrils were detected by fluorescence microscopy. The coaggregation process was observed by real-time 3D imaging using slit-scanning confocal microscopy, which showed a typical sigmoid curve with 1.5 h in the lag-time and 12 h until saturation. Inhibition of coaggregation using an anti-Abeta antibody can be observed as 3D images on a microscopic scale. Microglia ingested monomeric QDAbeta more significantly than oligomeric QDAbeta, and the ingested QDAbeta was mainly accumulated in the lysosome. CONCLUSIONS/SIGNIFICANCE These data demonstrate that QDAbeta is a novel nanoprobe for studying Abeta oligomerization and fibrillization in multiple modalities and may be applicable for high-throughput drug screening systems.
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Affiliation(s)
- Kiyotaka Tokuraku
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- Department of Chemical Science and Engineering, Miyakonojo National College of Technology, Miyakonojo, Japan
| | - Meg Marquardt
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Tsuneya Ikezu
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- * E-mail:
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